APA (7e ed.) Bronvermelding

Fowler, A. (2000). The virtuous spiral: A guide to sustainability for non-governmental organisations in international development. Earthscan.

Chicago (17e ed.) Bronvermelding

Fowler, Alan. The Virtuous Spiral: A Guide to Sustainability for Non-governmental Organisations in International Development. London ; Sterling, VA: Earthscan, 2000.

MLA (8e ed.) Bronvermelding

Fowler, Alan. The Virtuous Spiral: A Guide to Sustainability for Non-governmental Organisations in International Development. Earthscan, 2000.